#9858: Typeable instances should be kind-aware -------------------------------------+------------------------------------- Reporter: dreixel | Owner: Type: bug | Status: merge Priority: highest | Milestone: 7.10.2 Component: Compiler | Version: 7.9 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | typecheck/should_fail/T9858a, | should_run/T9858b | Blocking: | Differential Revisions: Phab:D652 -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"c0b5adbd1a04dd1c7916c1240e50a936e826136d/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="c0b5adbd1a04dd1c7916c1240e50a936e826136d" Do not decompose => (Trac #9858) We really don't want to unify (a b) with (Eq a => ty). The ever-ingenious Oerjan discovered this problem; see comment:101 in Trac #9858. See Note [Decomposing fat arrow c=>t] in Type.hs }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9858#comment:105> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler